Many general illumination light fixtures have incorporated light emitting diode (LED) light sources to produce light. Typically, light fixtures incorporating LEDs use heat sinks that are static and rigid to control the heat resulting from the use of LED light sources. The heat sink components often limit the design and configuration of the fixture itself, particularly with recessed and/or partially or fully enclosed light fixtures using LED light sources. Moreover, to accommodate the thermal tolerances of the fixture while rotating and/or aiming the LED light sources, directional LED based light fixtures often lower the power level supplied to the LED light sources to maintain proper thermal operating levels thereby decrease the efficiency advantages offered by using LED light sources versus conventional light sources (e.g., incandescent, fluorescent, etc.).
What is needed is a way to provide sufficient thermal control that allows for further design flexibility and/or greater efficiency (i.e., power efficiency, longer life of light source, etc.) when using LED light sources in light fixtures.